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c/hplc·submitted 1 year ago by u/rania_okonkwo

reading purity threads from 2024 and half of it aged badly

Labbranch of 6 comments

reading purity threads from 2024 and half of it aged badly — a position I have arrived at slowly and would like tested. A shoulder that does not baseline-resolve cannot be quantified honestly. You can report it as an unresolved shoulder, which is useful information, or you can develop the method until it resolves.…

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6 comments, started 1 year ago
u/matias_salgado102 points·1 year ago·edited

System suitability — repeat injections, tailing factor, plate count, RSD on area — is what tells you the instrument was fit for the measurement that day. Without it, the purity figure is unanchored.

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u/marit_mwangi29 points·1 year ago

System suitability — repeat injections, tailing factor, plate count, RSD on area — is what tells you the instrument was fit for the measurement that d

This is the whole methodological point of the board in one line.

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[deleted]11 points·1 year ago

[deleted]

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u/rosa_sandvik8 points·1 year ago

Small fix — 214nm, not 210. It matters for the comparison you are making with the other run.

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u/rania_okonkwoOP64 points·1 year ago

That is area percent, not mass percent. The trace cannot give you the second one.

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u/rania_okonkwoOP46 points·1 year ago

Can you post the trace with the axes labelled?

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